[Influence of the "aliasing" effect and the filter on the quantitative determination of the mean flow rate and flow volume per unit of time using the pulsed Doppler ultrasound method].

By the pulsed doppler ultra sound the blood flow volume will be measured by a discrete time signal. The consequences which are obtained for fourier's transformation are deduced and specially the problem "aliasing" for the quantitative measurement of the flow volume per time is discussed. The influence of the different filters on the quantification of the blood flow volume per time can be demonstrated by in-vitro measurements compared with the pulsed doppler combination of Kranzbühler (pulsed Doppler combination 8105, linear 8130) and the pulsed Doppler combination of Toshiba (pulsed Doppler combination SAL 50).